Builting open(), io classes, os and os.path functions and some other
functions in the stdlib support bytes paths as well as str paths. But
many functions doesn't. There are requests about adding this support
([1], [2]) in some modules. It is easy (just call os.fsdecode() on
argument) but I'm not sure it is worth to do. Pathlib doesn't support
bytes path and it looks intentional. What is general policy about
support of bytes path in the stdlib?
[1] http://bugs.python.org/issue19997
[2] http://bugs.python.org/issue20797